Spring



(No Model.)

W. I. BUNKER.

SPRING.

No. 319,555. Patented June 9,1885

INVENTOR' WITNESSES @m 4%7/ ATTORNEY Ilnrrnn @rares Parent? @entera WILLIAM I. BUNKER, OFVGIIICAGO, ILLINOIS.

SPRING.

SPECIFICATION forming part of Letters Patent No. 319,555, dated June 9, 1885.

Application filed January 27, 1985.

To all whom it may concern: p

Be it known that I, WILLIAM I. BUNKER, a citizen of the United States, residing at Chicago, Illinois, have inventedcertain new and useful Improvements in Springs, of which the following is a specification.

The object of my invention is to make a spring for buggies, carriages, Ste., which will be at the same time both a compression and an extension spring, and that will compensate for the wear or weakening of one portion by increasing the power and tension of another vportion of the spring.

In the drawings, Figure l is a view of my compound extension and compression spring detached. Fig. 2 is a perspective view of the same attached to the buggy axle and bed, and Fig. 3 is transverse sectional View of the axle and buggy-bed, showing the manner of attaching the spring to the same.

A represents the compression portion of the spring, and B the extension portion of the same; C, brackets for attachingV the spring to the different members of the desired object; C', end caps for the spring; D, a rod connecting such end caps; E, the buggy-axle, and F the buggy-bed.

In making my compound compression and extension spring I take a wire or rod of suitable size and make a number or series of coils which stand in their normal position apart from each other, and which come into contact only when positively compressed or forced together. After making the desired number of such coils I change the gage so that the coils lie contiguous to each other in their'normal state, and can only be separated by applying a positive pulling or extending force. After making the desired number or series of these coils I again change the gage and proceed to make a number or series of coils which stand separate and apart from each other in their normal position, so that they can onlyv be brought into contact by applying a positive compression force, as in the first instance. These coils are all along or around the same longitudinal axis. I then put in the brackets C by which the spring is to be attached to the different members of any desired object, and then place the caps C in place, compress the springs to the desired point, and fasten them in such position by the rod D, which extends (No model.)

through the coil and is suitably attached by nuts or otherwise to the end caps. In this way the ends ofthe spring are prevented from opening from each other beyond the predetermined distance and the weight distributed from one end to the other. As shown inthe drawings, this rod runs through the spring, but it could as well be placed ou the outside, as its office is simply to connect the two ends together, and when a nest of springs or a series, as in Fig. 2, are placed on the same horizontal plane the end caps may include all or any number of them, so that a separate rod for each spring would be unnecessary. 'Ihe spring is now completed and ready for use.

In illustrating the use of my compound spring I have chosen to do so in connection with a buggy axle and frame, though this is only one ofthe great Variety of uses to which the spring may be put, and in which I contemplate using it. tothe axle and bed of the buggy the principle of its operation will be fully and clearly illustrated. In thus applying it I attach the upper of the brackets O to the axle of the buggy by a square journal, as shown in Fig. 3, or in any other secure and suitable manner. The spring now stands in front of the buggy-axle, and to make the attachment to the buggybed the lower of the brackets C should be turned around to the opposite side of the spring and attached by bolts or screws to the buggy-body, as shown in Fig. 3. As the axle is held at a constant and invariable distance from the groundby the wheels, the upper brackets of the spring will of course be held constantly and invariably in the same relative position. As the Weight arising from the occupancy of the buggy by one or more persons is applied it will press the lower of the brackets C down and away from the other bracket, thus enlarging the distance between the two brackets and opening the coils, while at the same time it will be diminishing the distance between the lower bracket and the lower cap on the end of the spring and closing the coils between them. As these coils are being thus compressed the rod will distribute the weight to the upper cap on the spring and pull it down toward the upper bracket, thus correspondingly closing the coilsvand diminishing the distance between them. In this way it will be seen that as the In describing its attachment IOC l together. All portions of the spring will in this way assist in receiving and bearing the strain or Weight, in the one case by opening the coils and in the other by correspondingly closing them.

This is the principle or prime idea of theinvention, no matter to what uses the spring may be applied, whether to buggies, carriages, or other objects in which coiled springs may be used, though modiiications of this principle may be made-as, for instance, one of the compression portions of the spring may be omitted and only one compression and one extension portion of the spring be used together, or theseportions of the spring may be made to alternate with each other any number of times desired, or the compression portion of the spring may be placed in the middle 'and thev extension portion of the spring at the ends, or the respective portions of the spring may be made separately and connected at the brackets or inE any other convenient manner. In all these' various modifications, however, the' partsv are intended to operate with each other, so that as the coils of the extension portion of the spring are being opened the coils of the compressionv portion of the spring are being closed.

The particular advantages of my compound compression and extension spring over all j others now in use, so far as l know, are its compensating qualities and the safety which it affords from accidents by breakage. As the coils of the extension portion of the spring are openedthe coils of the compression portion are correspondingly closed, so that as the one 1 machine, of a compound compression and eX- part becomes weakened the increasing tension produced in the other parts affords sufficient i or lying against each other in a state of rest,

compensation to preserve the average strength and tension of the spring. It' either the coinpression or extension portion of the spring should become broken by a sudden strain or accident, the other portion ofthe spring would receive the weight and prevent the two parts of the object connected by the spring from becoming detached and separated.

1. As a new article of manufacture, a compound compression and extension spring comprising two or more series of coils around the Same longitudinal axis, the coils of one scribed.

3. As a new article of manufacture, a compound compression and extension spring, consisting of two or more series ofcoils around the same longitudinal axis, the coils of one series approaching each other in a state of rest, and requiring the vapplication of positive force to open or extend them, and the coils of the placed between end caps, pieces, or plates,

whereby the ends of the spring are prevented y from being separated beyond a predetermined distance, substantially as described.

5. The combination, in a compound compressionv and extension spring consisting of coils approaching or-lying against each other n in a state of rest, and coils opened or separated from each other in a state of rest, of end caps i or pieces and a connector between said end caps or pieces, substantially as described.

6. The combination, with a buggy or other tension spring `consisting of coils approaching and coils opened or separated from each other in a state of rest, and end caps or pieces to prevent the end coils from separating'from each other beyond a fixed predetermined distance, and brackets or connectors for securing and holding the spring to the connected parts or pieces, substantially as described.

WILLIAM I. BUNKER.

Vitnesses:

THoMAs A. BANNING, E. F. HUBBARD.

i other separating from each other in a stateof 7o g rest, and requiring the application of positive l force to close or compress them, substantially j' as described. l

4. As a new article of. manufacture, a coinpound compression and extension spring conf sisting of two or more series of coils around the same longitudinal axis, the coils of one sef ries being adapted to be extended and the coils of the other compressed, the whole being IOO 

